1. Field of the Invention
The present invention relates generally in-line skates and is particularly concerned with an in-line skate frame with a H-block or grinding insert.
2. Related Art
In-line skates typically have a series of wheels arranged one after the other in a single row or line in the running direction. The wheels are rotatably mounted on a frame, and the frame is connected to the sole of a shoe or skate boot, or may be integrated into the sole of the boot. The frame typically has a pair of side plates between which the wheels are mounted, and an upper portion with openings through which a frame bolt extends to attach the frame to the sole of a boot.
In some skates, particularly so-called extreme, aggressive, or stunt skates, the center of the lower edge of each plate is arched to provide a sliding surface for the skater to slide or grind along a railing, curbstone edge, or the like. This results in wear and eventually requires replacement of the entire frame. In some cases, a so-called “H-block” of different material is secured in a downwardly directed recess at the center of the frame, between two of the wheels, and has an arched, downwardly facing sliding surface. The H-block can be made of various different materials in order to provide faster or slower sliding surfaces. This avoids or reduces the risk of damage or abrasion to the frame itself during sliding or grinding. The H-block insert can be removed and replaced as necessary. A H-block insert device is described in my U.S. Pat. No. 6,581,943. The purpose of H-blocks is to provide an inexpensive solution to replace the part of the frame that wears down the most during stunts such as grinding.
One problem with some existing H-block insert designs is that the structure of the frame may be weakened by the cut-out or recess which is provided to accommodate mounting of the H-block insert and attachment of the insert to the frame. This cut-out makes the frame less stiff, so that it is more likely to bend and eventually crack. The pressure on the outside wheels on landing after a jump bends the frame and may eventually cause the frame to crack.